1. Field of the Invention
The present invention relates to an electrochemical deposition method, and more specifically, to an electrochemical deposition method for surface metallization.
2. Description of the Prior Art
With rapid development of electronic technology, electronic apparatuses have become indispensable products in daily life. To meet consumers' needs, many electronic apparatuses have powerful functions and pleasing appearance. For appearance, an electronic apparatus with a metal case has many advantages, such as high intensity, EMI (Electro Magnetic Interference) shielding, and good thermal conduction, so it is popular in the market. However, applications of metal cases are limited, as a manufacturing process is more complicated and has higher cost than for a plastic case. Therefore, surface metallization has arisen accordingly.
In general, an electro-plating method or an electro-molding method is utilized for surface metallization. However, both of the aforementioned methods have respective drawbacks. The electro-plating method involves plating a metal surface on a surface of a mold via an electrolytic process. That is to say, the electro-plating method involves disposition of a mold into an electrolytic bath and connection of the mold to a negative pole of a battery. In such a manner, metal ions with positive electrical charge in the electrolytic bath may receive electrons on the negative pole to generate a uniform metal layer on the surface of the mold. But, if a manufacturer wants to perform an extra surface effect treatment on the surface of the mold, the only way is to perform texture treatment on the surface of the mold before utilizing the electro-plating method. In other words, the electro-plating method cannot perform special surface effect treatments (such as a brushed surface or a laser pattern) on the surface of the mold by itself. Another method is the electro-molding method. The electro-molding method begins with generating an electro-molding part, and then the electro-molding part is glued to the surface of the mold for generating special surface effects on the surface of the mold. However, the overall thickness of the surface according to the said method is greater than the overall thickness of the surface according to the electro-plating method, since there is an adhesive layer present between the electro-molding part and the surface of the mold when performing the electro-molding method. Furthermore, compared with other related methods, the electro-molding method also has a problem of low connecting strength. In addition to the two aforementioned methods, a method of spraying metal lacquer can also be utilized for surface metallization, but it has problems of low yield, poor reflection, and lack of a metal feel.